Atmospheric pollutants

This question is about hydrocarbons.

A hydrocarbon has the formula C₆H₁₄

Name the two elements in a hydrocarbon.

How many atoms are there in one molecule of C₆H₁₄?

Tick (✓) one box.

C₆H₁₄ is a member of a homologous series.

What is the general formula for the homologous series that contains C₆H₁₄?

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Which homologous series has C₆H₁₄ as a member?

Tick (✓) one box.

Complete Figure 1 to show the displayed structural formula of C₆H₁₄

Petrol contains C₆H₁₄

Petrol is burned in car engines.

What general name is used to describe petrol when petrol is burned to release energy?

Atmospheric pollutants are formed when C₆H₁₄ undergoes incomplete combustion.

Complete the sentences.

Choose answers from the box.

The solid atmospheric pollutant formed during incomplete combustion of C₆H₁₄ is

The gaseous atmospheric pollutant formed during incomplete combustion of C₆H₁₄ is

A different organic compound (C₁₂H₂₆) can be broken down to produce C₆H₁₄ and one other compound.

Complete the equation for the reaction.

The percentage by mass of each element in C₆H₁₄ is:

Complete Figure 2.

You should:

• label each element on the x-axis

• plot the percentage by mass of C in C₆H₁₄

This question is about burning coal.

A power station has four coal-burning furnaces.

Each furnace burns 3000 kg of coal per minute.

Table 1 shows some information about this coal burning power station

Carbon dioxide is a greenhouse gas.

What is the effect on the rate of global climate change of using more furnaces in this power station?

Complete the sentence.

Choose the answer from the box.

The rate of global climate change

7000 kg of carbon dioxide are produced when 3000 kg of coal are burned.

Calculate the mass of carbon dioxide produced when 1 kilogram of coal is burned.

Complete the sentence.

Table 1 is repeated below.

Figure 3 shows how the mass of sulfur dioxide produced per minute varies with the mass of coal burned per minute.

Complete Figure 3.

You should:

plot data from Table 1 on Figure 3

draw a line of best fit.

Complete the sentence.

Use Table 1 and Figure 3.

As the mass of coal burned per minute increases, the mass of sulfur dioxide

produced per minute

This power station also releases particulates into the air.

Complete the sentence.

This question is about burning fuels in central heating boilers.

In the future, gas central heating boilers may burn hydrogen rather than natural gas.

Table 2 shows information about these fuels when 1 dm³ of the fuel is burned in a central heating boiler.

Explain how oxides of nitrogen are produced when burning fuels.

Explain one positive impact on the environment of burning hydrogen rather than natural gas as a fuel.

Use Table 2.

Explain one negative impact on the environment of burning hydrogen rather than natural gas as a fuel.

Use Table 2.

Air is 20% oxygen.

Calculate the volume of air needed to provide enough oxygen to react with 3.50 dm³ of hydrogen gas.

The equation for the reaction is

Central heating boilers can also burn kerosene.

Kerosene is produced from crude oil in a fractionating column using fractional distillation.

In the first step, crude oil is heated and hydrocarbon vapours are formed.

Explain how kerosene is produced from these hydrocarbon vapours.

This question is about fuels.

The energy produced by burning fuels is used to generate electricity in power stations.

Table 5 shows information about three fuels used to generate electricity.

Explain why coal is usually transported to power stations by train and not by pipeline.

Use Table 5.

Sulfur dioxide and particulates are atmospheric pollutants produced when fuels are burned.

1 kg of each fuel in Table 5 is burned.

Which fuel produces the most sulfur dioxide?

Give one reason for your choice.

Give one problem caused by sulfur dioxide.

Particulates are formed from solid particles.

1 kg of each fuel in Table 5 is burned.

Which fuel produces the least particulates?

Give one reason for your choice.

Give one problem caused by particulates.

Complete the sentence.

Figure 6 shows how the use of oil and of natural gas as fuels changed in the UK between 2002 and 2020.

Describe the trends shown in Figure 6.

This question is about the fractions obtained from crude oil.

Crude oil is separated into fractions by fractional distillation. The fractions obtained from crude oil include:

• lubricating oil

• naphtha

• petroleum gases.

Table 3 shows the boiling point range of these fractions.

Explain how these fractions are obtained from crude oil by fractional distillation.

Fractions from crude oil can be processed to produce feedstock for the petrochemical industry. Which two are useful materials produced from this feedstock? Tick (✓) two boxes.

Another fraction obtained from crude oil is petrol.

Petrol contains a hydrocarbon with the formula C₉H₂₀ Complete the equation for the complete combustion of C₉H₂₀ You should balance the equation.

Petrol obtained from crude oil contains sulfur impurities. Explain why sulfur impurities are removed before petrol is burned in car engines.

Table 4 shows information about two more fractions obtained from crude oil.

A student predicted that heavy fuel oil is more viscous than kerosene. The student’s prediction was correct.

Justify the student’s prediction.

The heavy fuel oil fraction can be processed to produce smaller hydrocarbon molecules.

Name the process which produces smaller hydrocarbon molecules from heavy fuel oil. Give the conditions used in this process.

Hydrocarbon molecules containing seven and eight carbon atoms can be produced when heavy fuel oil is processed. Which pair of hydrocarbon molecules would both turn bromine water colourless? Tick (✓) one box.

This question is about fuels and energy.

Figure 6 shows the percentage of electricity generated in the UK between 2007 and 2017 using:

• oil

• solar energy.

Describe the changes in the percentage of electricity generated in the UK between 2007 and 2017 using:

• oil

• solar energy.

Use data from Figure 6 in your answer.

Oil contains carbon and some sulfur.

When oil is burned, the products of combustion may be released into the atmosphere.

Explain the environmental effects of releasing these products of combustion into the atmosphere.

Suggest one reason why using solar energy is a more sustainable way of generating electricity than burning oil.

Solar energy may not be able to replace the generation of electricity from fossil fuels completely.

Suggest two reasons why.

This question is about fuels and energy. Figure 1 shows the percentage of electricity generated in the UK between 2007 and 2017 using:

• oil

• solar energy.

Describe the changes in the percentage of electricity generated in the UK between 2007 and 2017 using:

• oil

• solar energy.

Use data from Figure 1 in your answer.

Oil contains carbon and some sulfur. When oil is burned, the products of combustion may be released into the atmosphere. Explain the environmental effects of releasing these products of combustion into the atmosphere.

Suggest one reason why using solar energy is a more sustainable way of generating electricity than burning oil.

Solar energy may not be able to replace the generation of electricity from fossil fuels completely. Suggest two reasons why.

This question is about atmospheric pollution.

Figure 3 shows a limestone carving which has been damaged by atmospheric pollution.

The carving has been:

• blackened by soot

• eroded where the limestone has reacted with atmospheric pollutants.

What reacted with the limestone to cause the erosion?

Tick (✓) one box.

Soot is produced by the incomplete combustion of diesel oil.

Complete the sentences.

Choose answers from the box.

Complete the sentence.

Carbon monoxide is produced by the incomplete combustion of methane.

Balance the equation for the reaction.

2 CH₄ + 3 O₂ → ____ CO + 4 H₂O

Car engines work at high temperatures.

Complete the sentences.

Choose answers from the box.

In car engines, nitrogen is present.

The nitrogen in car engines comes from.

This reaction produces.

This question is about atmospheric pollution.

Figure 3 shows a limestone carving which has been damaged by atmospheric pollution. The carving has been:

• blackened by soot

• eroded where the limestone has reacted with atmospheric pollutants.

Explain why soot is formed when some fossil fuels are burned.

Fossil fuels are burned in car engines. Explain how reducing the amount of sulfur in fossil fuels reduces the erosion of limestone.

Oxides of nitrogen are atmospheric pollutants which are formed in car engines. Explain why oxides of nitrogen are formed in car engines.

Some central heating boilers use methane as a fuel.

Carbon monoxide detectors are placed near central heating boilers.

Which three properties of carbon monoxide make it necessary to use carbon monoxide detectors?

Choose answers from the box.

Complete the sentence.

Methane produces carbon monoxide when burning in a limited supply of

8 g of methane has a volume of 12 dm³ at room temperature and pressure.

Calculate the mass of 36 dm³ of methane.

Most methane is obtained from natural gas, which is a fossil fuel.

Methane can also be produced renewably.

Which two are renewable sources of methane?

Tick (✓) two boxes.

This question is about combustion of fuels.

Some central heating boilers use wood as a fuel.

Suggest two reasons why wood is more sustainable than natural gas as a fuel for central heating boilers.

Natural gas is mainly methane.

When methane burns it can produce both carbon monoxide and carbon dioxide.

Explain the process by which carbon monoxide can be produced when methane is burned.

Balance the equation for the combustion of methane to produce carbon monoxide.

Propane burns to form carbon dioxide and water.

The equation for the reaction is:

3.60 dm³ carbon dioxide is produced when a sample of propane is burned in

Calculate the volume of unreacted oxygen.

Give your answer in cm³

Older cars are tested each year to measure the amount of pollutants contained in exhaust fumes. Table 4 shows the maximum allowed percentages of exhaust pollutants for petrol cars.

Explain how carbon monoxide is produced when petrol is burned in car engines.

Suggest two reasons why the maximum allowed percentage of carbon monoxide has been decreased for newer cars.

Give one reason for having a maximum allowed percentage of unburned hydrocarbons in exhaust fumes.

Oxides of nitrogen are also pollutants contained in exhaust fumes.

Describe how oxides of nitrogen are produced when petrol is burned in car engines.

Catalytic converters are fitted to car exhausts to reduce the amount of pollutants released into the atmosphere.

Nitrogen dioxide is an oxide of nitrogen. Nitrogen dioxide reacts to produce nitrogen and oxygen in catalytic converters. Complete the equation for this reaction. The equation should be balanced.

Give two effects of atmospheric pollution which are reduced by using catalytic converters.

The catalyst in catalytic converters is a mixture of three elements. Where in the periodic table are these elements most likely to be found?

Tick one box.